This work aims to develop an innovative shock wave lithotripsy (SWL) technology for improved stone fragmentation with reduced tissue injury. This innovative technology is based on recent in vitro study findings that stone fragmentation during SWL can be significantly enhanced by improving energy concentration towards the target concretions, through the controlled, forced collapse of cavitation bubbles. This improvement, when optimized in in vivo conditions, can substantially reduce the exposure of stone patients to high-intensity shock waves during SWL, while still maintaining effective stone comminution. This improvement will both greatly shorten the treatment time and lower the potential risk for renal tissue injury, thus improving the cost-effectiveness of lithotripsy procedure. Since this novel technology can be added as an upgrade on existing lithotripters, the potential for rapid clinical application of this innovation is very promising. We propose a systematic investigation to develop this innovative SWL technology. Specific aims include: 1) controlled, forced collapse of cavitation bubbles during SWL; 2) modification of existing shock wave generators;3) in vitro; and 4) in vivo evaluation of this innovative SWL technology. We will use high-speed photography, acoustic emission measurements, combined with stone/tissue phantoms and animals studies to identify the optimal shock wave parameters for producing maximum energy concentration on target concretions, with minimal adverse effects on surrounding renal tissue. Direct comparison of this novel shock wave lithotripsy technology with novel currently in use, in terms of stone fragmentation efficiency and tissue injury, will also be carried out.